How to prepare for INMO

Since INMO is coming up, it would be nice to write a post about it! A lot of people have been asking me for tips.

To people who are visiting this site for the first time, hi! I am Sunaina Pati, an undergrad student at Chennai Mathematical Institute. I was an INMO awardee in 2021,2022,2023. I am also very grateful to be part of the India EGMO 2023 delegation. Thanks to them I got a silver medal!

I think the title of the post might be clickbait for some. What I want to convey is how I would have prepared for INMO if I were to give it again. Anyway, so here are a few tips for people!

Practice, practice, practice!!

I can not emphasize how important this is. This is the only way you can realise which areas ( that is combinatorics, geometry, number theory, algebra) are your strength and where you need to work on.
Try the problems as much as you want, and make sure you use all the ideas you can possibly think of before looking at a hint. So rather than fixing time as a measure to decide to give up on a problem, fix ideas as the measure. Obviously, you would have to decide if you are out of ideas or not. Essentially, through each problem, you should try to maximize your learning, while minimizing your time. Again, I am not implying that you should spend less time on each problem, but since time one has limited time to spend each day, it would be ideal to try to minimise the time spent while maximizing the amount of knowledge you gain.
There is no fixed threshold/ requirement for the amount of time you should spend every day to become an INMO awardee. While this might be a concern for a lot of people, my advice to them should be to not think about this question and rather just focus on problem-solving whenever you can. Also, time spent is a continuous function rather than being discrete. At least for me and many other things, we usually think about a math problem almost all the time, consciously or subconsciously. Hence, this question is very hard to answer.

But practice from where??

Another question which I get asked a lot is "Where should I practice problems. Could you recommend some sources?". Again, pretty subjective answer. Moreover, please note that whatever I say shall not be a "requirement".
I would like to be comfortable in solving IMO shortlist problems of indexes 1,2 and 3. And for my strong areas, at least 6. I also feel INMO and Russian, USA and Iranian olympiads have a very similar flavour as INMO and I would have liked to solve those problems. They look very fun! Additionally, definitely INMO, IMO, EGMO, APMO and RMM problems.
I also joined OTIS ( by Evan Chen), and the problems in those problem sets/ handouts were great! I would love to try harder problems and be more confident.
Another advice, I would give to everyone is to not be intimidated by a problem because of the source and rather give it an honest try. Moreover, do not restrict yourself to these particular sources and just try the problems you love. Remember, it is not about the quantity but the ideas you gain while trying to solve these problems. The ideas which you get but do not work. They are equally important.

Wait, what about theory?????

So, for the books, here is a list of books/ handouts which you can try!

1. Evan Chen’s Handouts and his book EGMO

2. Alex Remerov’s Handouts

3. Yufei Zhao’s Handouts

4. Rohan Goyal's Handouts ( Rg's handouts can be found here )

5. Modern Olympiad Number Theory by Aditya Khurmi

6. Additionally, the Online math club's Youtube channel is a really good source to learn from! Please do check it out :)

7. And maybe this blog too! It has a lot of problems which you can try :)

Please, do not be intimidated at all by the theory and remember that math olympiads are truly mostly about problem-solving.

Any final advice??

A few actually. Practice mocks and timed exams. Time pressure is real and it's nicer to get used to it.
Try to not make "winning gold at IMO" your goal but rather learning a lot of new math and solve problems your goal. Not saying the former is bad, but it is pretty stressful and take the fun out of it.
Try solving problems in a group as it is an extremely fun experience. You get to meet and talk to people who are just like you. It makes your journey fun!
Do not be stressed and never compare yourself with others. This journey is yours and simply yours.

~Sunaina

Comments

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Sunaina thinks absurd

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